7.20 The roof of a refrigerated truck compartment is of com- posite construction, consisting of a layer of foamed urethane insulation (1₂ = 50 mm, k, = 0.026 W/m.K) sandwiched between aluminum alloy panels (t₁ = 5 mm, kp = 180 W/m.K). The length and width of the roof are L = 10 m and W = 3.5 m, respectively, and the temper- ature of the inner surface is T, = -10°C. Consider con- ditions for which the truck is moving at a speed of V = 105 km/h, the air temperature is T.. = 32°C, and the solar irradiation is Gs = 750 W/m². Turbulent flow may be assumed over the entire length of the roof. T₁0 V.I FC Frank & Dave s Frozen Desserts for Those Who Dent Count Calories Tu 2, a (a) For equivalent values of the solar absorptivity and the emissivity of the outer surface (α = ε = 0.5), estimate the average temperature T of the outer surface. What is the corresponding heat load imposed on the refrigeration system? (b) A special finish (α = 0.15, & = 0.8) may be applied to the outer surface. What effect would such an application have on the surface temperature and the heat load? (c) If, with a = e = 0.5, the roof is not insulated (1₂ = 0), what are the corresponding values of the surface temperature and the heat load?

Elements Of Electromagnetics
7th Edition
ISBN:9780190698614
Author:Sadiku, Matthew N. O.
Publisher:Sadiku, Matthew N. O.
ChapterMA: Math Assessment
Section: Chapter Questions
Problem 1.1MA
icon
Related questions
Question
7.20 The roof of a refrigerated truck compartment is of com-
posite construction, consisting of a layer of foamed
urethane insulation (1₂ = 50 mm, k, = 0.026 W/m.K)
sandwiched between aluminum alloy panels (t₁ = 5 mm,
kp = 180 W/m.K). The length and width of the roof are
L = 10 m and W = 3.5 m, respectively, and the temper-
ature of the inner surface is T, = -10°C. Consider con-
ditions for which the truck is moving at a speed of
V = 105 km/h, the air temperature is T.. = 32°C, and the
solar irradiation is Gs = 750 W/m². Turbulent flow may
be assumed over the entire length of the roof.
T₁0
V.I
FC
Frank & Dave s
Frozen Desserts for Those Who
Dent Count Calories
Tu
2, a
(a) For equivalent values of the solar absorptivity and
the emissivity of the outer surface (α = ε = 0.5),
estimate the average temperature T of the outer
surface. What is the corresponding heat load imposed
on the refrigeration system?
(b) A special finish (α = 0.15, & = 0.8) may be applied
to the outer surface. What effect would such an
application have on the surface temperature and the
heat load?
(c) If, with a = e = 0.5, the roof is not insulated
(1₂ = 0), what are the corresponding values of the
surface temperature and the heat load?
Transcribed Image Text:7.20 The roof of a refrigerated truck compartment is of com- posite construction, consisting of a layer of foamed urethane insulation (1₂ = 50 mm, k, = 0.026 W/m.K) sandwiched between aluminum alloy panels (t₁ = 5 mm, kp = 180 W/m.K). The length and width of the roof are L = 10 m and W = 3.5 m, respectively, and the temper- ature of the inner surface is T, = -10°C. Consider con- ditions for which the truck is moving at a speed of V = 105 km/h, the air temperature is T.. = 32°C, and the solar irradiation is Gs = 750 W/m². Turbulent flow may be assumed over the entire length of the roof. T₁0 V.I FC Frank & Dave s Frozen Desserts for Those Who Dent Count Calories Tu 2, a (a) For equivalent values of the solar absorptivity and the emissivity of the outer surface (α = ε = 0.5), estimate the average temperature T of the outer surface. What is the corresponding heat load imposed on the refrigeration system? (b) A special finish (α = 0.15, & = 0.8) may be applied to the outer surface. What effect would such an application have on the surface temperature and the heat load? (c) If, with a = e = 0.5, the roof is not insulated (1₂ = 0), what are the corresponding values of the surface temperature and the heat load?
Expert Solution
trending now

Trending now

This is a popular solution!

steps

Step by step

Solved in 4 steps with 4 images

Blurred answer
Knowledge Booster
Convection
Learn more about
Need a deep-dive on the concept behind this application? Look no further. Learn more about this topic, mechanical-engineering and related others by exploring similar questions and additional content below.
Similar questions
Recommended textbooks for you
Elements Of Electromagnetics
Elements Of Electromagnetics
Mechanical Engineering
ISBN:
9780190698614
Author:
Sadiku, Matthew N. O.
Publisher:
Oxford University Press
Mechanics of Materials (10th Edition)
Mechanics of Materials (10th Edition)
Mechanical Engineering
ISBN:
9780134319650
Author:
Russell C. Hibbeler
Publisher:
PEARSON
Thermodynamics: An Engineering Approach
Thermodynamics: An Engineering Approach
Mechanical Engineering
ISBN:
9781259822674
Author:
Yunus A. Cengel Dr., Michael A. Boles
Publisher:
McGraw-Hill Education
Control Systems Engineering
Control Systems Engineering
Mechanical Engineering
ISBN:
9781118170519
Author:
Norman S. Nise
Publisher:
WILEY
Mechanics of Materials (MindTap Course List)
Mechanics of Materials (MindTap Course List)
Mechanical Engineering
ISBN:
9781337093347
Author:
Barry J. Goodno, James M. Gere
Publisher:
Cengage Learning
Engineering Mechanics: Statics
Engineering Mechanics: Statics
Mechanical Engineering
ISBN:
9781118807330
Author:
James L. Meriam, L. G. Kraige, J. N. Bolton
Publisher:
WILEY